Experimental Study of Resistive Bistability in Metal Oxide Junctions

TL;DR

This study investigates resistive bistability in metal oxide junctions, emphasizing reproducibility and endurance, with TiO2 showing promising results for potential use in hybrid electronic circuits.

Contribution

It provides a comparative analysis of resistive bistability in various metal oxide junctions and demonstrates fabrication improvements to enhance device performance.

Findings

Resistive bistability observed in NbOx, CuOx, TiOx junctions

TiO2 junctions exhibit endurance over 1000 switching cycles

Reproducibility remains a challenge for large-scale integration

Abstract

We have studied resistive bistability (memory) effects in junctions based on metal oxides, with a focus on sample-to-sample reproducibility which is necessary for the use of such junctions as crosspoint devices of hybrid CMOS/nanoelectronic circuits. Few-nm-thick layers of NbOx, CuOx and TiOx have been formed by thermal and plasma oxidation, at various deposition and oxidation conditions, both with or without rapid thermal post-annealing (RTA). The resistive bistability effect has been observed for all these materials, with particularly high endurance (over 1000 switching cycles) obtained for single-layer TiO2 junctions, and the best reproducibility reached for multi-layer junctions of the same material. Fabrication optimization has allowed us to improve the OFF/ON resistance ratio to about 1000, but the sample-to-sample reproducibility is so far lower than that required for large scale integration.